Interface system for a television receiver

ABSTRACT

An interface system for a television receiver includes an interface connector having a plurality contacts connected to various component circuits in the television receiver. In order to provide various functions for the television receiver, the interface system includes various circuit boards each having a plug connectable with the interface connector. The plug includes a number of contacts equal to or less than the plurality of contacts in the interface connector. Depending on the desired function, the circuit board further includes circuits for providing the function, these circuits being interconnected and connected to the appropriate contacts in the plug for connecting with the appropriate component circuits in the television receiver. The interface system allows the television receiver functions to be modified and/or updated without the need for opening the television and modifying the circuits and/or the wiring to the circuits.

BACKGROUND OF THE INVENTION

1. Field of The Invention

The subject invention relates to television receivers and the variousfunctionality options now available to a user.

2. Description of The Related Art

Television receivers that are being marketed today have various optionalfunctions which may be incorporated therein. For example, the televisionreceiver may include Picture-in-Picture (PIP) in which the video signalfor PIP is provided by a second signal source (a VCR) connected to asecond video input of the television receiver, or a second tuner so thatthe television receiver may by itself provide PIP. These and otheroptional features are provided by modifying the circuitry inside thetelevision receiver. Quite naturally, these changes must be implementedin the production line resulting in a plurality of different models ofthe television receiver being fabricated. It should be apparent thatthis results in relatively high production costs. In marketing theseseparate models of television receivers, a dealer must then anticipatewhat features his/her customers would desire, and order sufficientquantities of the specific models. Any others must be orderedspecifically for that consumer which may result in a lost sale.

In another situation, unless the particular model of television receiverin the user's possession has the appropriate features, the user mustopen up the television receiver, and cut into existing wiring so thatthe user may be able to adapt the television receiver for use with, forexample, a computer.

SUMMARY OF THE INVENTION

It is an object of the present invention to devise a standard televisionreceiver which is easily adaptable for different functionalities.

It is a further object of the present invention to provide a standardtelevision receiver in which the different functionalities may beadapted without opening the television receiver and physically modifyingthe circuitry therein.

The above objects are achieved in an interface system for a televisionreceiver, said television receiver comprising a tuner for receiving andselectively tuning to a television signal, a deflection circuit coupledto said tuner for generating deflection signals from synchronizationsignals contained in said television signal, an audio signal processingcircuit coupled to said tuner for processing an audio signal containedin said television signal, a video signal processing circuit coupled tosaid tuner for processing a video signal contained in said televisionsignal, and a display coupled to said deflection circuit and said videosignal processing circuit for displaying said video signal in dependenceon said deflection signals, characterized in that said interface systemcomprises:

standard bus means having M leads separately connected to said audiosignal processing circuit, said deflection circuit and said video signalprocessing circuit, where M is an integer greater than one;

connector means having M contacts connected, respectively, to said Mleads in said standard bus means; and

circuit board means accessible by a user of said television receiver,said circuit board means having plug means connectable to said connectormeans, said plug means having N contacts corresponding, respectively, toat least some of the M contacts in said connector means, where N is aninteger less than or equal to M, and circuit means connected to said Ncontacts in said plug means, said circuit means, when connected throughsaid plug means, said connector means and said standard bus means to atleast one of the audio signal processing circuit, the video signalprocessing circuit and the deflection circuit in the televisionreceiver, modifies the operation of said television receiver therebyproviding additional features for the user.

As shown in FIG. 1, the interface system of the subject invention allowsa television receiver to be modified and/or upgraded to variousdifferent functionalities including: CD-Video, CD-i, television/computerinterface, ghost cancellation, dual tuner PIP, digital compressed videocable interface, hotel/motel/hospital pay-per-view system, etc., just byplugging the appropriate circuit board into the interface connector.

BRIEF DESCRIPTION OF THE DRAWINGS

With the above and additional objects and advantages in mind as willhereinafter appear, the invention will be described with reference tothe accompanying drawings, in which:

FIG. 1 shows the various different applications for the interface systemof the subject invention;

FIG. 2 shows, in block diagram form, a standard television receiver, inwhich the interface system is used to provide a second video source anda second PIP;

FIG. 3 shows, in block diagram form, the standard television receiver,in which the interface system is used to provide ghost cancellation;

FIG. 4 shows, in block diagram form, the standard television receiver,in which the interface system is used to provide a hospitality product;

FIG. 5 shows, in block diagram form, the standard television receiver,in which the interface system is used to interface the televisionreceiver with a digital compressed video cable system;

FIG. 6 shows the system of FIG. 5, with the exception that analog RGBsignals are being provided; and

FIG. 7 shows how the interface system is mounted in the housing of atelevision receiver.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 2 shows a standard television receiver 10 having an input 12 forreceiving television signals from, for example, an antenna 14. The input12 is connected to a tuner 16 for tuning the television to a particulartelevision signal. The output from the tuner 16 is connected, on the onehand, to an audio signal processing circuit 18 which separates an audiosignal from the received television signal and generates signals forapplication to speakers 20. The audio signal processing circuit 18includes a stereo decoder 22 which decodes the audio signal in thetelevision signal from the tuner 16 into separate left and right audiosignals, in which case the speakers include a left and a right speakerfor receiving the amplified left and right audio signals. The outputfrom the tuner 16 is also applied to a deflection circuit 24 forgenerating deflection signals from the synchronization signals containedin the television signal, and to a video signal processing circuit 26for processing the video signal contained in the television signal intocomponent signals for application to CRT driver circuits 28 for drivinga cathode ray tube (crt) 30, which receives the deflection signals fromthe deflection circuit 24. The video signal processing circuit 26 alsoincludes an on-screen display circuit 32 for providing video signalsindicating messages for display of the crt 30. As noted in FIG. 2, aninfrared remote control transmitter 34 is shown for interaction with aremote control receiver 36 in the television receiver 10. Amicrocomputer 38 is also shown which controls the operation of the otherelements in the television receiver 10. Finally, a power supply circuit40 is shown which provides operating power to each of the abovecircuits. It should be noted that the connecting lines between thesecomponents have been omitted for clarity, any one skilled in the artwould know how each of these circuits would be interconnected.

The subject invention includes the provision of a standard bus havinglines 44 connected to each of the above-noted components. These lines 44are then connected to contacts 46 in an interface connector 48. Acircuit board 50 is then provided with a plug 52 having contacts 54 forengaging with the contacts 46 in the interface connector 48. Inparticular, depending on the functionalities to be offered by theparticular circuit board 50, various of the contacts 54 in the plug 52are connected to circuits 56 mounted on the circuit board 50. Inparticular, as shown in FIG. 2, these circuits 56 include a second tuner56.1, a PIP IC 56.2, and a DRAM 56.3. The contacts 54 being used in theplug 52 connect with the contacts 46 in the interface connector 48connected to the power supply circuit 40, the deflection circuit 24, thevideo signal processing circuit 26, and the microcomputer 38. The powersupply circuit 40 supplies power to the second tuner 56.1, the PIP IC56.2 and the DRAM 56.3. Then, under control of the microcomputer 38, thevideo signal processing circuit 26 provides the main video signal to thePIP IC 56.2 on the circuit board 50. Based on the television signalbeing tuned with the second tuner 56.1 which, for this purpose, isconnected to an RF input 58 mounted on the circuit board 50, this signalis inserted into the main video signal as a PIP signal and the combinedvideo signal is sent to a PIP circuit 60 in the video signal processingcircuit 26 for presenting the main video signal and the PIP video signalas, for example, two side-by-side PIP images. FIG. 2 further shows theremote control receiver 36 also being connected to a contact 48 on theinterface connector 48 for connecting with a contact 54 in the plug 52which, in turn, is connected to the circuit board 50. This enablesremote control signals to be processed both by a remote control circuit(not shown) on the circuit board 50 as well as by the microcomputer 38,depending upon the nature of the remote control signal being received.

FIG. 3 shows an embodiment in which the interface system provides ghostcancellation. In particular, the circuit board 50' includes a ghostcancellation IC 62 which receives power from the power supply circuit40. Under control of a signal from the microcomputer 38, the videosignal processing circuit 26 provides the video signal to the ghostcancellation IC 62 which then applies a ghost-free video signal back tothe video signal processing circuit 26

FIG. 4 shows an embodiment in which the interface system provides ahospitality product. In particular, hospitals, hotels, motels, etc. maywant the feature of being able to provide pay-per-view service. Thishospitality functionality is provided by a circuit board 50" which issubstantially similar to circuit board 50' with the exception that theghost cancellation IC 62 is replaced by a hospital IC 62' which receivesfurther control signals from the microcomputer 38.

In FIG. 5, an embodiment is shown in which the interface system providesthe capability of receiving and processing compressed digital videosignals from, for example, a cable system which includes means fordecryption of "premium" scrambled signals provided by the cablesupplier. In particular, the circuits 56 on the circuit board 50'"include a tuner/QAM/VSB front end 64, a transport 66, a digitalvideo/audio decoder (e.g., MPEG 2) 68 with an associated DRAM 70, adigital NTSC encoder 72, an on-screen display and/or CD-i graphics andDRAM 74, an audio interface circuit 76, a microcomputer 78 including anFSK modem 80, an input/output port 82 for the cable, and a port 84 forreceiving a decryption card 86. These separate circuits areinterconnected as shown in FIG. 5 and are connected through contacts 54on the plug 52 and contacts 46 in the interface connector 48 to thepower supply circuit 40, the microcomputer 38, the audio signalprocessing circuit 18, and the video signal processing circuit 26. Itshould be noted that the contacts 46 on the interface connector 48 forthe power supply circuit 40 and the microcomputer 38 are the same forall the embodiments of FIGS. 2-4. However, while the embodiments ofFIGS. 2 and 3 provide a CBVS (composite) video signal for the videosignal processing circuit 26, the embodiment of FIG. 5 provides separateluminance and chrominance component signals for improved pictureperformance. Hence, these signals are provided on contacts 46/54separate from those that carry the composite video signal of FIGS. 2 and3. Additionally, the embodiments of FIGS. 2 and 3 did not concern audio.Hence, while the audio signal processing circuit 18 is connected to theinterface connector 48 in all cases, only here in FIG. 4 is there aconnection from the audio interface circuit 76 to the respectivecontacts 54 on the plug 52 on the circuit board 50'".

The embodiment of FIG. 6 is substantially similar to that of FIG. 5 withthe exception that instead of the digital NTSC encoder 72, thisembodiment includes an RGB matrix interface 88 which provide analog RGBsignals. Again, separate contacts 54 are used on the plug 52 whichconnect with respective contacts 46 on the interface connector 48connected to respective inputs of the video signal processing circuit26.

As shown in FIG. 7, the interface connector 48 may mounted in a recessedarea 90 in the back panel 92 of the housing 94 of the televisionreceiver. A separate cover 96 attached to the appropriate circuit board50 containing the circuits 56 and the plug 52 engages with the backpanel 92 of the housing 94 as the plug 52 engages with the interfaceconnector 48 thereby closing the recessed area 90. Alternatively, thecircuit board 50 is inserted into the recessed area 90 separate from thecover 96 until the plug 52 engages the interface connector 48. The cover96 is then positioned over the recessed area 90.

Numerous alterations and modifications of the structure herein disclosedwill present themselves to those skilled in the art. However, it is tobe understood that the above described embodiment is for purposes ofillustration only and not to be construed as a limitation of theinvention. All such modifications which do not depart from the spirit ofthe invention are intended to be included within the scope of theappended claims.

What is claimed is:
 1. An interface system for a television receiver,said television receiver comprising a tuner for receiving andselectively tuning to a television signal, a deflection circuit coupledto said tuner for generating deflection signals from synchronizationsignals contained in said television signal, an audio signal processingcircuit coupled to said tuner for processing an audio signal containedin said television signal, a video signal processing circuit coupled tosaid tuner for processing a video signal contained in said televisionsignal, a display coupled to said deflection circuit and said videosignal processing circuit for displaying said video signal in dependenceon said deflection signals, and a power supply circuit for supplyingoperating power to each of the above components, characterized in thatsaid interface system comprises:standard bus means having M leadsseparately connected to said audio signal processing circuit, saiddeflection circuit, said video signal processing circuit and said powersupply circuit, where M is an integer greater than one; connector meanshaving M contacts connected, respectively, to said M leads in saidstandard bus means; and circuit board means accessible by a user of saidtelevision receiver, said circuit board means having plug meansconnectable to said connector means, said plug means having N contactscorresponding, respectively, to at least some of the M contacts in saidconnector means, where N is an integer less than or equal to M, andcircuit means connected to said N contacts in said plug means, saidcircuit means, when connected through said plug means, said connectormeans and said standard bus means to at least one of the audio signalprocessing circuit, the video signal processing circuit, the deflectioncircuit and the power supply circuit in the television receiver,modifies the operation of said at least one of the audio signalprocessing circuit, the video signal processing circuit, the deflectioncircuit and the power supply circuit in the television receiver, wherebyadditional features are provided for the user.
 2. An interface system asclaimed in claim 1, wherein said television receiver further comprises aremote control receiver for receiving remote control signals from aremote control transmitter, and a microcomputer for controlling saidtelevision receiver at least partly in response to signals from saidremote control receiver, characterized in that said standard bus meansincludes leads separately connected to said remote control receiver andsaid microcomputer, said remote control receiver and said microcomputerbeing connected to said circuit board means by said connector means andsaid plug means so that said remote control signals may be processed bysaid circuit means on said circuit board means, and said circuit meanson said circuit board means being controlled by said microcomputer. 3.An interface system as claimed in claim 1, wherein said interface systemprovides a source for a further television signal, and wherein saidvideo signal processing circuit includes a picture in picture (PIP)circuit for processing said further television signal as a PIP signal,characterized in that the circuit means on said circuit board meansincludes a further tuner connected to an RF input on said circuit boardmeans for tuning to said further television signal, a PIP IC coupled toan output of said further tuner, and a DRAM connected to said PIP IC,said further tuner and said PIP IC having power and control inputsconnected to contacts in said plug means which in turn connect withcontacts in said interface connector means connected to said powersupply circuit and a microcomputer in said television receiver, and saidPIP IC having signal inputs and outputs connected to contacts in saidplug means which, in turn, connect with contacts in said interfaceconnector means connected to signal outputs of said video signalprocessing circuit and signal inputs of said PIP circuit, whereby, undercontrol of said microcomputer, said further television signal beingtuned by said further tuner is inserted into a main video signal, tunedby said tuner in said television receiver and supplied by said videosignal processing circuit, as a PIP signal, and the combined videosignal is sent to the PIP circuit in the video signal processing circuitsuch that the video signal tuned by said tuner and the furthertelevision signal tuned by said further tuner appear in a same pictureframe.
 4. An interface system as claimed in claim 1, wherein saidinterface system provide ghost cancellation for said televisionreceiver, and said television receiver further includes a microcomputerfor controlling functions of the television receiver, characterized inthat said circuit means on said circuit board means include a ghostcancellation IC having power and control inputs connected to contacts insaid plug means for connecting with contacts in said interface connectormeans connected to said power supply circuit and said microcomputer insaid television receiver, said ghost cancellation IC further havingsignal inputs and outputs connected to contacts in said plug means forconnecting with contacts in said interface connector means connected tooutputs and inputs, respectively, in said video signal processingcircuit, whereby under control of said microcomputer, said video signalprocessing circuit provides a video signal to said ghost cancellation ICand said ghost cancellation IC provides a ghost-free version of saidvideo signal back to said video signal processing circuit.
 5. Aninterface system as claimed in claim 1, wherein said interface systemenables said television receiver to receive and process compresseddigital video signals, and said television receiver further includes amicrocomputer for controlling functions of said television receiver,characterized in that the circuit board means includes an RF input forreceiving said compressed digital video signals modulated on RFcarriers, a further tuner coupled to said RF for tuning in one of saidRF carriers, a front end coupled to an output of said further tuner forprocessing said RF carrier and for providing said compressed digitalvideo signals, a transport coupled to an output of said front end forselectively unscrambling said compressed digital video signals, adecompression circuit coupled to an output of said transport fordecompressing said compressed digital video signals, and an encodercoupled to an output of said decompression circuit for providingseparated luminance and chrominance component signals, said circuitboard means further including an audio interface coupled to outputs ofsaid decompression circuit for providing digital audio signals, adescrambling circuit coupled to inputs and outputs of said transportcircuit for descrambling the compressed digital video signals, and afurther microcomputer coupled to said descrambling circuit forcontrolling the descrambling circuit, and coupled to a graphics controlcircuit for generating graphics for display, said graphics controlcircuit being connected to an input of said encoder, said circuit boardmeans further including a modem coupled to said RF input fortransmitting signal from said further microcomputer, each of saidelements having power and control inputs connected to contacts of saidplug means for connecting with contacts in said interface connectormeans connected to said power supply circuit and said microcomputer, andsaid audio interface and said encoder include signal outputs connectedto contacts in said plug means for connecting with contacts in saidinterface connector means connected with inputs in said audio signalprocessing circuit and said video signal processing circuit.
 6. Aninterface system as claimed in claim 5, characterized in that saidencoder alternatively provides analog RGB signals which are applied toseparate contacts in said plug means for connecting with contacts insaid interface connector means connected with analog RGB inputs in saidvideo signal processing circuit. .Iadd.
 7. A television receiver for usein a television interface system, said television interface systemcomprising said television receiver and circuit board means accessibleby a user of said television receiver for connection to said televisionreceiver, said television receiver comprising a tuner for receiving andselectively tuning to a television signal, a deflection circuit coupledto said tuner for generating deflection signals from synchronizationsignals contained in said television signal, an audio signal processingcircuit coupled to said tuner for processing an audio signal containedin said television signal, a video signal processing circuit coupled tosaid tuner for processing a video signal contained in said televisionsignal, a display coupled to said deflection circuit and said videosignal processing circuit for displaying said video signal in dependenceon said deflection signals, and a power supply circuit for supplyingoperating power to each of the above components, and said circuit boardmeans comprising circuit means for connecting to at least one of theaudio signal processing circuit, the deflection circuit and the powersupply circuit in the television receiver for modifying the operation ofsaid television receiver thereby providing additional features for theuser, characterized in that said television receiver furthercomprises:standard bus means having M leads separately connected to saidaudio signal processing circuit, said deflection circuit, said videosignal processing circuit and said power supply circuit, where M is aninteger greater than one; and connector means having M contactsconnected, respectively, to said M leads in said standard bus means, forconnecting said television receiver to said circuit boardmeans..Iaddend..Iadd.8. A television receiver as claimed in claim 7,wherein said television receiver further comprises a remote controlreceiver for receiving remote control signals from a remote controltransmitter, and a microcomputer for controlling said televisionreceiver at least partly in response to signals from said remote controlreceiver, characterized in that said standard bus means includes leadsseparately connected to said remote control receiver and saidmicrocomputer, thereby enabling said circuit means on said circuit boardmeans to process said remote control signals, and said circuit means tobe controlled by said microcomputer..Iaddend..Iadd.9. Circuit boardmeans for use in a television interface system, said televisioninterface system comprising a television receiver and said circuit boardmeans accessible by a user of said television receiver for connection tosaid television receiver, said television receiver comprising a tunerfor receiving and selectively tuning to a television signal, adeflection circuit coupled to said tuner for generating deflectionsignals from synchronization signals contained in said televisionsignal, an audio signal processing circuit coupled to said tuner forprocessing an audio signal contained in said television signal, a videosignal processing circuit coupled to said tuner for processing a videosignal contained in said television signal, a display coupled to saiddeflection circuit and said video signal processing circuit fordisplaying said video signal in dependence on said deflection signals, apower supply circuit for supplying operating power to each of the abovecomponents, standard bus means having M leads separately connected tosaid audio signal processing circuit, said deflection circuit, saidvideo signal processing circuit and said power supply circuit, where Mis an integer greater than one; and connector means having M contactsconnected, respectively, to said M leads in said standard bus means,characterized in that said circuit board means comprises: plug meansconnectable to said connector means, said plug means having N contactscorresponding, respectively, to at least some of the M contacts in saidconnector means, where N is an integer less than or equal to M; andcircuit means connected to said N contacts in said plug means, wherebywhen said circuit means is connected through said plug means, saidconnector means and said standard buss means to at least one of theaudio signal processing circuit, the video signal processing circuit,the deflection circuit and the power supply circuit in the televisionreceiver, said circuit means modifies the operation of said televisionreceiver thereby providing additional features for a user of thetelevision receiver..Iaddend..Iadd.10. Circuit board means as claimed inclaim 9, wherein said television receiver further comprises a remotecontrol receiver for receiving remote control signals from a remotecontrol transmitter, and a microcomputer for controlling said televisionreceiver at least partly in response to signals from said remote controlreceiver, and wherein said standard bus means includes leads separatelyconnecting said remote control receiver and said microcomputer tocontacts in said connector means, characterized in that said circuitmeans on said circuit board means are connectable through said plugmeans, said connector means and said standard bus to said remote controlreceiver and said microcomputer such that remote control signals may beprocessed by said circuit means, and said circuit means are controllableby said microcomputer..Iaddend..Iadd.11. Circuit board means as claimedin claim 9, wherein said interface system provides a source for afurther television signal, and wherein said video signal processingcircuit includes a picture-in-picture (PIP) circuit for processing saidfurther television signal as a PIP signal, characterized in that thecircuit means on said circuit board means includes a further tunerconnected to an RF input on said circuit board means for tuning to saidfurther television signal; a PIP IC coupled to an output of said furthertuner; and a DRAM connected to said PIP IC, said further tuner and saidPIP IC having power and control inputs connected to contacts in saidplug means which, in turn, are connectable with contacts in saidconnector means connected to said power supply circuit and amicrocomputer in said television receiver, and said PIP IC having signalinputs and outputs connected to contacts in said plug means which, inturn, are connectable with contacts in said connector means connected tosignal outputs of said video signal processing circuit and signal inputsof said PIP circuit, whereby, under control of said microcomputer, saidfurther television signal tuned by said further tuner may be insertedinto a main video signal, tuned by said tuner in said televisionreceiver and supplied by said video signal processing circuit, as a PIPsignal, the combined video signal being sent to the PIP circuit in thevideo signal processing circuit such that the video signal tuned by saidtuner and the further television signal tunable by said further tunermay appear in a same picture frame..Iaddend..Iadd.12. Circuit boardmeans as claimed in claim 9, wherein said interface system providesghost cancellation for said television receiver, and said televisionreceiver further includes a microcomputer for controlling functions ofthe television receiver, characterized in that said circuit means onsaid circuit board means includes a ghost cancellation IC having powerand control inputs connected to contacts in said plug means forconnecting with contacts in said connector means connected to said powersupply circuit and said microcomputer in said television receiver, saidghost cancellation IC further having signal inputs and outputs connectedto contacts in said plug means for connecting with contacts in saidconnector means connected to outputs and inputs, respectively, in saidvideo signal processing circuit, whereby, under control of saidmicrocomputer, said video signal processing circuit may provide a videosignal to said ghost cancellation IC and said ghost cancellation IC mayprovide a ghost-free version of said video signal back to said videosignal processing circuit..Iaddend..Iadd.13. Circuit board means asclaimed in claim 9, wherein said interface system enables saidtelevision receiver to receive and process compressed digital videosignals, and said television receiver further includes a microcomputerfor controlling functions of said television receiver, characterized inthat the circuit board means includes an RF input for receiving saidcompressed digital video signals modulated on RF carriers; a furthertuner coupled to said RF input for tuning in one of said RF carriers; afront-end circuit coupled to an output of said further tuner forprocessing said RF carrier and for providing said compressed digitalvideo signals; a transport circuit coupled to an output of saidfront-end circuit for selectively unscrambling said compressed digitalvideo signals; a decompression circuit coupled to an output of saidtransport circuit for decompressing said compressed digital videosignals; and an encoder coupled to an output of said decompressioncircuit for providing separated luminance and chrominance componentsignals, said circuit board means further including an audio interfacecoupled to outputs of said decompression circuit for providing digitalaudio signals; a descrambling circuit coupled to inputs and outputs ofsaid transport circuit for descrambling the compressed digital videosignals; and a further microcomputer coupled to said descramblingcircuit for controlling the descrambling circuit, said furthermicrocomputer also being coupled to a graphics control circuit forgenerating graphics for display, said graphics control circuit beingconnected to an input of said encoder, said circuit board means furtherincluding a modem coupled to said RF input for transmitting signal fromsaid further microcomputer, each of said elements having power andcontrol inputs connected to contacts of said plug means for connectingwith contacts in said connector means connected to said power supplycircuit and said microcomputer, and said audio interface and saidencoder include signal outputs connected to contacts in said plug meansfor connecting with contacts in said connector means connected withinputs in said audio signal processing circuit and said video signalprocessing circuit..Iaddend..Iadd.14. Circuit board means as claimed inclaim 13, characterized in that said encoder alternatively providesanalog RGB signals which are applied to separate contacts in said plugmeans for connecting with contacts in said connector means connectedwith analog RGB inputs in said video signal processing circuit..Iaddend.